JPH0350011B2 - - Google Patents

Description

[Detailed description of the invention]

FIELD OF THE INVENTION The present invention relates to a feed yarn for the production of composite textured yarns, in particular a feed yarn comprising polyamide filaments, and a process for simultaneous stretching and false twisting of the feed yarn. (Prior Art) False-twisting thermoplastic long fiber yarns to form bulky yarns has been practiced for a long time. This method is very convenient because a large bulky yarn can be obtained with relatively simple processing, but on the other hand, the texture of the processed yarn is monotonous and tends to be artificial. Therefore, a method of simultaneously false twisting multiple yarns has been proposed as a method to more closely resemble the texture of natural spun. For example, as shown in Fig. 3, the raw yarn 1 is false-twisted in a false twisting device 5, and the raw yarn 2 is fed thereto so as to be wound thereon while overfeeding, set in a heater 6, and then untwisted. In this method, a core-sheath two-layer composite yarn 8 is produced. However, this method
It has the disadvantage that the point where the raw yarn 2 meets the yarn 2 tends to become unstable (on the contrary, knotted yarn can also be used), and advanced techniques are required to obtain a well-balanced yarn without knots. Furthermore, since threads having different feeding speeds are threaded at the same time, it requires skill to operate. In an attempt to improve this, the supply yarn 1 and the supply yarn 2' are simultaneously fed as shown in FIG. By increasing the elongation (significantly higher elongation), the raw yarn 2' can easily stretch around the raw yarn 1 when false-twisted.
A method was proposed to create a two-layer structure by winding the fibers. This made it possible to create a two-layer structure with simultaneous yarn feeding, improving processing stability and operability.
In this case, if the degree of molecular orientation of yarn 2' is lowered too much, the fibers may deteriorate, resulting in poor durability, decreased dye fastness, or a dyeing difference between yarn 1 and yarn 2'. They tend to get bigger and make the appearance worse. In particular, for polyamide fibers, if the degree of molecular orientation of the raw yarn 2' is significantly lowered (the cutting elongation is significantly increased), an excellent cotton-like feel can be obtained, but the color fastness is significantly reduced. It deteriorates and becomes unusable. In order to improve this color fastness, it is sufficient to increase the molecular orientation of the raw yarn 2', but in the case of polyamide, unlike polyester, etc., there is a region where it self-extends due to the influence of moisture during spinning and winding. This region varies depending on the polymer composition, denier structure, and spinning conditions, but
In the case of No. 6, the spinning speed is approximately 1300 to 3500 m/min and the elongation at break of the spun yarn is 200 to 70%, and winding cannot be carried out industrially in this range. On the other hand, in the so-called high-speed spinning region where the spinning speed is 3500 m/min or more (the elongation at break is 70% or less), it becomes possible to wind the material again. However, with a composite false-twisted yarn of yarn 2', which has an elongation at break of about 70%, and yarn 1, which has an even lower elongation at break than yarn 2', the color fastness is satisfied, but the texture deteriorates. However, polyamide multifilament yarns having a breaking elongation of 70 to 200 percent are desired. (Objective of the Invention) The present invention is to put into practical use a polyamide multifilament yarn having a breaking elongation of 70 to 200 percent, which was conventionally considered impossible to use, in a state suitable for composite processing. A further object of the present invention is to provide a core-sheath two-layer composite yarn that is highly dye fast and exhibits a cotton-like texture. (Structure of the Invention) According to the present invention, (1) a self-extending polyamide multifilament having a breaking elongation of 70 to 200 percent;
Co-spun is a low elongation polyamide multifilament whose breaking elongation is 30% or more lower than the polyamide multifilament.
and (2) a self-extending polyamide multifilament having a breaking elongation of 70 to 200 percent. and,
Co-spun is a low elongation polyamide multifilament whose breaking elongation is 30% or more lower than the polyamide multifilament.
Provided is a method for producing a false-twisted two-layer textured yarn, which comprises subjecting a conjugate fiber obtained by taking the composite fiber by simultaneously drawing and false-twisting the composite fiber by intertwining 2/M or more fibers. Ru. The present invention will be explained in further detail. The composite fiber of the present invention includes at least one component of a polyamide multifilament having a breaking elongation of 70 to 200 percent. This polyamide multifilament yarn becomes a sheath component of a two-layer processed yarn in false twisting processing, etc., and by using polyamide as such a high elongation component, a natural cotton-like woven or knitted fabric can be obtained. Even if other polymers such as polyester are used, a cotton-like material cannot be obtained. Further, the elongation at break of this polyamide multifilament is preferably 80 to 150%. When the elongation is less than 70%, not only is it difficult to obtain a two-layer textured yarn, but also a cotton-like woven or knitted fabric cannot be obtained, and at the same time, a deep color cannot be obtained. On the other hand, if it exceeds 200%, a two-layer textured yarn can be easily obtained, but the color fastness is poor and it is no longer practical. Next, the other component of the composite fiber of the present invention must have a breaking elongation lower than that of the polyamide multifilament by at least 30%, and more preferably by at least 50%. If this difference is less than 30%, a processed yarn with a sufficient two-layer structure cannot be obtained, and therefore a cotton-like woven or knitted fabric texture cannot be obtained. Note that any thermoplastic synthetic fiber such as polyester, polyolefin, polyamide, etc. can be used as this low elongation component, but if a polymer that is different from the high elongation component in terms of dyeability is used, it will create a weave with a heather effect. A knitted fabric is obtained. Moreover, if the same polyamide polymer is used, a good product with excellent level dyeing properties can be obtained. In this case, the cutting elongation of the low elongation component must be adjusted to 70% or less to prevent elongation due to moisture. Furthermore, the composite fiber of the present invention is composed of a polyamide multifilament and a multifilament having a cutting elongation lower than that of the polyamide multifilament, which is composited by 2/M or more, preferably 10 or more, and more preferably 20 or more intertwined parts. ing. If the number of confounds between two components is less than 2/M, 2
If the components are not sufficiently combined, the two components will separate during winding or processing, and problems such as winding failure or poor supply will easily occur. From this point of view, the degree of entanglement is more preferably 10 pieces/M or more. In addition, if the number of entangled parts is 20/M or more, separation of the two components in the processed yarn can be prevented, and a two-layer structured yarn with improved handling properties can be produced without using a new interlacing device during processing and supply. . Next, the method for manufacturing the composite fiber of the present invention will be described. In the case of the polyamide component used in the present invention, such as polycapramide, the yarn having a breaking elongation of 70 to 200 percent self-extends by absorbing moisture after spinning, and therefore cannot be industrially wound. especially,
When attempting to draw an undrawn yarn having a breaking elongation of 200 percent or more to adjust the elongation to 70 to 200 percent, it is necessary to carry out hot drawing at a very low speed, which is almost impossible industrially. Therefore, the present inventors studied the problem of how to wind a polyamide multifilament having a breaking elongation of 70 to 200 percent, and
It has been found that the above-mentioned problem can be solved by winding up a composite material that is entangled with a component that does not self-extend due to moisture. For example, as shown in FIG. 1, a yarn 1 having a low elongation component is melted and extruded from a spinneret 10 having a plurality of discharge ports using a polymer co-spun.
1' is stretched by two pairs of rollers 13' and 13 having different circumferential speeds to a region where it does not self-extend, while the high elongation component is stretched by a roller 14 whose speed is set to a spinning speed region where the cutting elongation is 70 to 200%. ', 14, and then the interlacing device 15 intertwines and combines the fibers and winds them up. This method can be easily adopted. As another method, as shown in FIG. 2, the low elongation component 11' is spun using a normal spinning method, and the high elongation component is focused by a focusing guide 17 immediately after the discharged polymer is cooled and solidified. However, it is also possible to adopt a method of high-speed spinning, entanglement, and winding while reducing air resistance. Furthermore, various methods can be employed, such as heat treating one component after spinning to lower the elongation, interlacing and compounding, and winding. It is also possible to adopt a method of adjusting the cutting elongation of the two components by changing the size of the die. The die 1 is for melt-extruding the same nylon polymer, and the inside of the die is formed with two or more independent extrusion zones, one of which extrudes polyamide.
Any means known in the art may be used, such as discharging polyamide or other polymers from other zones. Core-sheath false twisting 2 using the composite fiber provided by the present invention
To obtain the layered yarn, a normal false twisting machine capable of drawing and false twisting may be used. What is important here is to maintain the draw ratio during processing at least 1.05 (the upper limit is about 1.30), so that the low elongation yarn is relatively concentrated in the core.
Further, a two-layer structured yarn is obtained in which the high elongation yarn is wound around the core portion as a sheath component. In this case, if the number of entanglements at the composite yarn stage is set to 20/M, a so-called interfacial entangled structure will occur where both filaments are intertwined with each other at the interface between the core and sheath of the two-layered yarn even after processing. A two-layered yarn with a stable structure and excellent handling properties can be obtained. (Operations and Effects of the Invention) According to the present invention, there is provided a polyamide-based conjugate fiber that has color fastness and is useful for obtaining a false-twisted two-layer structured yarn having a cotton-like texture. Here, in order to obtain a false-twisted two-layer structured yarn having a polyamide yarn as a sheath component by drawing and false-twisting, a difference in elongation is required in the starting yarn. However, in the case of polyamide, the high elongation component is in the self-stretching range and cannot be wound in reality. There was nothing. In this regard, according to the present invention, although it was impossible to wind it due to self-stretching, it is possible to wind it without self-stretching by using a polyamide filament with a high elongation component that satisfies cotton-like texture and color fastness. Since the fibers are interlaced and composited with a low elongation component and then wound, a desired raw yarn for processing (composite fiber) can be realized. Furthermore, since the composite fiber of the present invention has a polyamide multifilament as a sheath component and a multifilament yarn as a core component of the two-layer processed yarn as an integral composite, it is necessary to supply the two components individually during processing. The creel space and supply yarn storage area are reduced, and troubles such as misplacement of the supply yarn can be prevented. (Example) Example 1 Polycapramide having an intrinsic viscosity [η] of 1.08 and containing 0.3 weight percent titanium oxide was melted at 253°C using the apparatus shown in Figure 1A, and then a cap with a diameter of 0.3 and 20 holes was formed. Two pieces were extruded at the same time. After the extruded polymer is cooled, one multifilament yarn is stretched between rollers 4, 4' and 5, 5' after applying an oil agent, and the other multifilament yarn is taken up by rollers 5, 5' after applying an oil agent, and stretched between rollers 5, 5'. ，
After the two components were combined on 5', they were entangled in an interlacing device 6, and then wound into cheese. At this time, the speeds of rollers 4, 4' and rollers 5, 5' were variously changed,
Composite fibers having the cutting elongation characteristics shown in Table 1 were obtained by variously changing the air pressure supplied to the entangling device. or,
The results of individual winding are also shown. The discharge amount was adjusted so that each of the two components had a denier of 40 denier after winding. In the present invention, the cutting elongation and the degree of entanglement are measured by the following method. Cutting elongation: Measured length 5 cm, tensile speed 20 using an Instron type tensile tester manufactured by Instron.
cm/min, chart speed 20cm/min, initial load 0.1
When measuring in g/de, the low elongation component is the second
In the figure, L is the cutting elongation, and the high elongation component is shown as the average of 5 times, with H being the cutting elongation. Degree of entanglement: A load of 1 g/de is applied to the sample, and the
A de hook was inserted between the single threads and a mark was made at the hooked part, and the number of marks per meter was averaged over 5 times.

【table】

[Table] Furthermore, the composite yarn obtained in Table 1 was manufactured by ARCT.
Machining speed 400m/min using FTF-483-6F machine,
Heater temperature 155℃, 3-axis ceramic disk,
Stretching and false twisting was performed at D/Y2.0. The stretching ratio was adjusted to 1.05 to 1.30 and the processing tension was adjusted to 18 to 20 g. Table 2 shows the evaluation results of the two-layer structure composite state of the obtained processed yarn and the weaving quality, texture, and color fastness of the fabric. The evaluation was conducted by five experts who gave excellent (◎), good (○),
The results are evaluated on a four-level scale of slightly poor (△) and poor (×) and averaged.

[Table] As is clear from Table 1, polyamides with a breaking elongation of 70 to 200%, which conventionally cannot be rolled by themselves,
By combining it with a component that does not self-extend, it becomes possible to wind it. Furthermore, as is clear from Table 2, by simultaneously stretching and false twisting the conjugate fibers of the present invention, it is possible to produce woven or knitted fabrics with excellent hand feel and excellent color fastness. As is clear from this example, the texture and color fastness of a woven or knitted fabric depend on the cutting elongation of the polyamide multifilament, which is the sheath component of the composite processed yarn of the composite fiber supplied for processing, and the low elongation component, which is the core component. The difference with the cutting elongation is dominant, and the cutting elongation of the sheath component is 70
~200%, and the difference in cutting elongation with the low elongation component is 30% or more, more preferably 50%.
It is necessary to adjust it by more than %. Further, the composite fiber of the present invention can prevent unraveling troubles during processing by having 2 or more entangled parts/M, more preferably 10 or more per M. Furthermore, if the number of intertwined parts is 20/M or more, excellent workability, weavability, and texture of the woven or knitted fabric can be obtained without additional intertwining treatment before processing.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of the process for explaining an example of manufacturing the conjugate fiber of the present invention, Fig. 2 is a chart for measuring the cutting elongation of the conjugate fiber of the present invention, and Figs. FIG. 2 is a schematic diagram of a composite false twisting process. In FIG. 1, 10: spinneret, 11: low elongation component, 11': polyamide high elongation component, 12:
Oil application device, 13, 13', 14, 14': roller, 15: entangling device, 16: winder, third
In Figure 4, 1: core yarn component raw yarn, 2,
2': Sheath component yarn, 3, 4: Supply roller, 5:
false twisting device, 6: heater, 7: take-up roller,
8: Composite processed yarn, 9: Winder.

Claims (1)

[Scope of Claims] 1 A self-extensible polyamide multifilament with a breaking elongation of 70 to 200% and a low elongation polyamide multifilament with a breaking elongation of 30% or more lower than the polyamide multifilament are cospun. 1. A composite fiber, which is obtained by co-spun, and is composited by intertwining 2/M or more. 2. The composite fiber according to claim 1, which has a difference in elongation of 50% or more. 3. The composite fiber according to claim 1, which has a degree of entanglement of 10 pieces/M or more. 4 A self-extensible polyamide multifilament with a breaking elongation of 70 to 200% and a low elongation polyamide multifilament with a breaking elongation of 30% or more lower than the polyamide multifilament are produced by co-spun. 1. A method for producing a false-twisted two-layer textured yarn, which comprises subjecting the composite fibers which are taken and composited by intertwining 2/M or more at the same time to simultaneous stretching and false-twisting. 5. The method for producing a false twisted two-layer textured yarn according to claim 4, wherein the stretching ratio is 1.05 to 1.30. 6. The method for producing a false-twisted two-layer structured yarn according to claim 4, wherein the composite fibers are further entangled before simultaneous stretching and false twisting.